Extremely odd indeed.

Al-Wāqidī said: ʿAbd Allāh ibn Jaʿfar narrated to us, from Ibn Abī ʿAwn, from Abū ʿAtīq, from Jābir ibn ʿAbd Allāh, who said:
“Water was lightly sprinkled over the Prophet’s grave—peace and blessings be upon him. Bilāl ibn Rabāḥ was the one who sprinkled it, using a waterskin. He began at the Prophet’s head, on the right side, and continued until he reached his feet; then he flung the water toward the wall, for he could not move all the way around because of it.”

Saʿīd ibn Manṣūr (1) reported, through al-Dārāwardī, from Sharīk (2) ibn ʿAbd Allāh ibn Abī Namr, from Abū Salamah, who said: “The Messenger of Allah died on Monday and was buried on Tuesday.”

Ibn Khuzaymah said: Salm ibn Junādah (3) narrated to us, from his father, from ʿUbayd (4) Allāh ibn ʿUmar, from Kurayb, from Ibn ʿAbbās, who said: “The Messenger of Allah died on Monday and was buried on Tuesday.”

Al-Wāqidī also said: ʿUbayy ibn ʿAbbās ibn Sahl ibn Saʿd (5) narrated to me, from his father, who said: “The Messenger of Allah—peace and blessings be upon him—died on Monday and was buried on the night before Tuesday.”

Abū Bakr ibn Abī al-Dunyā, on the authority of Muḥammad ibn Saʿd (6), stated: “The Messenger of Allah died on Monday, twelve nights having elapsed from Rabīʿ al-Awwal, and was buried on Tuesday.”

ʿAbd Allāh ibn Muḥammad ibn Abī al-Dunyā (7) said: Al-Ḥasan ibn Isrāʾīl Abū Muḥammad al-Nahartīrī narrated to us, ʿĪsā ibn Yūnus narrated to us, from Ismāʿīl ibn Abī Khālid, who said: I heard ʿAbd Allāh ibn Abī Awfā say, “The Messenger of Allah—peace and blessings be upon him—died on Monday and was not buried until Tuesday.” The same was also stated by Saʿīd ibn al-Musayyib, Abū Salamah ibn ʿAbd al-Raḥmān, and Abū Jaʿfar al-Bāqir.

Section (9)
A Description of His Grave, peace and blessings be upon him

It is known by mass-transmitted, unbroken consensus that he—peace and blessings be upon him—was buried in ʿĀʾishah’s chamber, which was reserved for her, on the eastern side of his mosque.